The metallurgical flowsheet for steel DL05 is hot metal- PB desulphurization treatment- BOF- argon blowing- RH- 200 mm x 200 mm blooms casting-rolled to Φ6. 5 mm rod products. The effect of produced 256 heats steel DL05 chemical composition on electric conductivity ratio is analyzed

it is obtained that with increasing total content of elements in steel or increasing Mn content in steel the electric conductivity ratio decreases

but with increasing the total content elements (except Mn) the electric conductivity ratio of steel increases not obviously

therefore the effect of Mn content in steel on electric conductivity ratio is greatest. And improving the cleanliness of steel is available to improve the electric conductivity ratio of steel. With optimizing the chemical composition original control range o£ steel DL05- /% : ≤0.10C

≤0. 10Si

≤0. 35Mn

≤0. 030P and ≤0. 030S to the control range- /% : ≤0. 02C

≤0. 03Si

≤0. 12Mn

≤0. 025P and ≤0. 015S

and effectively controlling the cleanliness of steel during RH refining

the 256 heats examination results show that the percentage of heats of electric conductivity ratio ≥16% increases from original 63. 25% to 93. 75%.